# Is RESET* on the XMEGA disabled when using the PDI interface?

When PDI CLK is connected on the XMEGA (also the RESET*) pin, can this pin still be used to trigger a reset on the chip? If so, how does the chip tell the difference between PDI being used as a clock and a genuine reset signal? Every document I have found on this matter is somewhat vague about what happens to the rest functionality of the pin when PDI is used.

If my wording is vague, what I am basically asking is if the reset pin can be used to reset the chip, if the firmware on the XMEGA was loaded via the PDI interface. I have a project that needs to be able to be reset in the field, but I also want to use the PDI interface to load the firmware on it from the factory.

You can still use it as /RESET. See this application note from Equinox for some details, or Atmel's own application note describing the PDI interface, if you'd prefer to get it straight from the source.